Apple is testing the personal assistant application Siri that was launched with the iPhone 4S on older mobile products, according to reports.
The company touted Siri as a major reason to upgrade to its latest handset, but the feature may become backwards compatible.
The tip-off comes via blog Jailbreaknation, citing a source “close to Apple” as saying the company had given sample handsets running Siri to employees to test out behind closed doors.
“Currently, it only runs on the iPhone 4S, but Apple has given employees access to a special software version that incorporates Siri’s features on to older devices,” the site said.
“Hackers and developers are currently working for a port, but if Apple releases this in a software update any time soon, they may not need to.”
Last week, the site poured water on Apple's claims that Siri needed the iPhone 4S's two cores in order to run by showing the assistant app running on an iPhone 4.
The company has reportedly since taken the trial handsets back in-house in a bid to avoid the costly security problems seen when the prototypes of the iPhone 4 and iPhone 4S were left in bars.
Both incidents led to embarrassing episodes as Apple struggled to get its hands back on the devices, and Apple's vice president of global security, John Theriault, has parted company with the iPhone manufacturers, apparently over the issue.
Although Apple has since told AllThingsD that Theriault has retired, there are widespread rumours that leaks surrounding iPhone launches meant he was pushed to leave the firm.
Theriault was a key figure in the investigation into the lost iPhone 4S prototype that saw Apple employees accused of impersonating police officers in order to gain access to a suspect's house.
This article originally appeared at pcpro.co.uk